From a72ea4ff359622c92d8115b6a0f0763aa65a04f1 Mon Sep 17 00:00:00 2001
From: Armin Friedl <dev@friedl.net>
Date: Sat, 30 Jul 2022 22:56:37 +0200
Subject: [PATCH] Final render

---
 rtiww/src/main.cpp | 82 +++++++++++++++++++++++++++++++++-------------
 1 file changed, 60 insertions(+), 22 deletions(-)

diff --git a/rtiww/src/main.cpp b/rtiww/src/main.cpp
index 25394c0..7e111d2 100644
--- a/rtiww/src/main.cpp
+++ b/rtiww/src/main.cpp
@@ -11,6 +11,52 @@
 #include <iostream>
 #include <memory>
 
+hittable_list random_scene() {
+  hittable_list world;
+
+  auto ground_material = make_shared<lambertian>(color(0.5, 0.5, 0.5));
+  world.add(make_shared<sphere>(point3(0, -1000, 0), 1000, ground_material));
+
+  for (int a = -11; a < 11; a++) {
+    for (int b = -11; b < 11; b++) {
+      auto choose_mat = random_double();
+      point3 center(a + 0.9 * random_double(), 0.2, b + 0.9 * random_double());
+
+      if ((center - point3(4, 0.2, 0)).length() > 0.9) {
+        shared_ptr<material> sphere_material;
+
+        if (choose_mat < 0.8) {
+          // diffuse
+          auto albedo = color::random() * color::random();
+          sphere_material = make_shared<lambertian>(albedo);
+          world.add(make_shared<sphere>(center, 0.2, sphere_material));
+        } else if (choose_mat < 0.95) {
+          // metal
+          auto albedo = color::random(0.5, 1);
+          auto fuzz = random_double(0, 0.5);
+          sphere_material = make_shared<metal>(albedo, fuzz);
+          world.add(make_shared<sphere>(center, 0.2, sphere_material));
+        } else {
+          // glass
+          sphere_material = make_shared<dielectric>(1.5);
+          world.add(make_shared<sphere>(center, 0.2, sphere_material));
+        }
+      }
+    }
+  }
+
+  auto material1 = make_shared<dielectric>(1.5);
+  world.add(make_shared<sphere>(point3(0, 1, 0), 1.0, material1));
+
+  auto material2 = make_shared<lambertian>(color(0.4, 0.2, 0.1));
+  world.add(make_shared<sphere>(point3(-4, 1, 0), 1.0, material2));
+
+  auto material3 = make_shared<metal>(color(0.7, 0.6, 0.5), 0.0);
+  world.add(make_shared<sphere>(point3(4, 1, 0), 1.0, material3));
+
+  return world;
+}
+
 color ray_color(const ray &r, const hittable &world, int depth) {
   hit_record rec;
 
@@ -35,43 +81,34 @@ int main() {
 
   // Image
 
-  const auto aspect_ratio = 16.0 / 9.0;
-  const int image_width = 400;
+  const auto aspect_ratio = 3.0 / 2.0;
+  const int image_width = 1200;
   const int image_height = static_cast<int>(image_width / aspect_ratio);
-  const int samples_per_pixel = 100;
+  const int samples_per_pixel = 500;
   const int max_depth = 50;
 
   // World
 
-  hittable_list world;
-
-  auto material_ground = make_shared<lambertian>(color(0.8, 0.8, 0.0));
-  auto material_center = make_shared<lambertian>(color(0.1, 0.2, 0.5));
-  auto material_left = make_shared<dielectric>(1.5);
-  auto material_right = make_shared<metal>(color(0.8, 0.6, 0.2), 0.0);
-
-  world.add(
-      make_shared<sphere>(point3(0.0, -100.5, -1.0), 100.0, material_ground));
-  world.add(make_shared<sphere>(point3(0.0, 0.0, -1.0), 0.5, material_center));
-  world.add(make_shared<sphere>(point3(-1.0, 0.0, -1.0), 0.5, material_left));
-  world.add(make_shared<sphere>(point3(-1.0, 0.0, -1.0), -0.4, material_left));
-  world.add(make_shared<sphere>(point3(1.0, 0.0, -1.0), 0.5, material_right));
+  auto world = random_scene();
 
   // Camera
 
-  point3 lookfrom(3, 3, 2);
-  point3 lookat(0, 0, -1);
+  point3 lookfrom(13, 2, 3);
+  point3 lookat(0, 0, 0);
   vec3 vup(0, 1, 0);
-  auto dist_to_focus = (lookfrom - lookat).length();
-  auto aperture = 2.0;
+  auto dist_to_focus = 10.0;
+  auto aperture = 0.1;
+
   camera cam(lookfrom, lookat, vup, 20, aspect_ratio, aperture, dist_to_focus);
 
   // Render
 
   std::cout << "P3\n" << image_width << " " << image_height << "\n255\n";
 
+  picture p;
+
+  #pragma omp parallel for shared(p)
   for (int j = image_height - 1; j >= 0; --j) {
-    std::cerr << "\rScanlines remaining: " << j << ' ' << std::flush;
     for (int i = 0; i < image_width; ++i) {
       color pixel_color(0, 0, 0);
       for (int s = 0; s < samples_per_pixel; ++s) {
@@ -80,10 +117,11 @@ int main() {
         ray r = cam.get_ray(u, v);
         pixel_color += ray_color(r, world, max_depth);
       }
-      write_color(std::cout, pixel_color, samples_per_pixel);
+      p.set_pixel(j,i,pixel_color);
     }
   }
 
+  p.write(std::cout, image_height, image_width, samples_per_pixel);
   std::cerr << "\nDone.\n";
   return 0;
 }